Field of the Invention
The present invention relates to a communication apparatus that is capable of performing facsimile communication, a control method therefor, and a storage medium storing a control program therefor.
Description of the Related Art
Conventionally, there is a technique of storing a facsimile signal in order to specify a cause of an obstacle, such as a communication error occurred during facsimile communication.
For example, there is a technique of storing a digital voice signal into which a voice file generation unit converts an analog voice signal, such as a facsimile signal D/A-converted by a facsimile modem, and transmitting the stored signal to a center apparatus through the Internet to analyze an obstacle in facsimile communication using a public network of a circuit switching system (see Japanese Laid-Open Patent Publication (Kokai) No. 2006-332889 (JP 2006-332889A)).
However, the conventional technique mentioned above A/D-converts an analog voice signal, which is D/A-converted by the facsimile modem, into a digital signal by the voice file generation unit. Thus, since there are two conversions between an analog signal and a digital signal, noise in the voice signal increases and accuracy of the voice signal drops.
On the other hand, a technique of providing a service through a LAN (Local Area Network) or an NGN (Next Generation Network) by replacing the conventional public network of the circuit switching system with a network based on an IP (Internet Protocol) technique will spread increasingly from now on.
An SIP (Session Initiation Protocol) that provides a service while a virtual session is established among a plurality of communication devices connected through the LAN or the NGN spreads, and is used.
Among the communication devices among which the session is established by the SIP, facsimile communication with a VoIP (Voice over IP) deemed voice is performed using a protocol, such as a VoIP.
However, since this case uses VoIP communication, there is no need for outputting an analog voice signal to a public line. This causes a problem that a facsimile signal that is a voice signal cannot be recorded and stored.